JPH07138846A - Weft tip holder in jet loom - Google Patents

Abstract

PURPOSE:To provide the holder ensuring bright specks not to be developed as a result that the weft tension of a woven fabric on the opposite picking side overcome warp tension. CONSTITUTION:While a picking fluid is yet acting on the tip of a weft, an electromagnet 35 is excited to '-' state to make its pole identical with that of a permanent magnet 32 to energize a holding member 26 toward the side of a second holding member 25, and the tip of the weft 1 picked by a jet fluid from a picking nozzle is held with these holding members 25, 26. Just before beating up, the pole of the electromagnet 35 is made to differ from that of the permanent magnet 32 to effect attraction of the holding member 26 with the electromagnet 35, thus the holding of the tip is released and the weft is relaxed to balance in tension between the weft and a warp.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weft end holding device for a jet loom.

[0002]

2. Description of the Related Art In a jet loom, particularly when a strongly twisted yarn is used as a weft yarn, it is necessary to keep the end portion of the weft yarn in a tensioned state in order to prevent the weft from losing tension after weft insertion. is there.

For this reason, a weft end holding device as disclosed in Japanese Utility Model Laid-Open No. 4-78287 has been proposed. this is,
A pair of holding members (plate-shaped body made of elastic material) having an opening and a contact portion is arranged at the arrival position of the weft end on the side opposite to the weft insertion side, and jet water for weft insertion that has entered into the opening portion comes into contact with The contact is released by passing through to form a weft flight path, and after passing the jet water, they are in contact with each other. Further, as disclosed in Japanese Utility Model Laid-Open No. 61-20584, a catching plate is attached to a sley in a state where it is inserted between the reeds outside the warp row on the side where the weft is inserted. It is known that the weft yarn is held from the non-holding position to the weft holding position, and is returned from the weft holding position to the non-holding position after beating.

[0004]

However, according to the former technique, the pair of holding members are in contact with each other after passing the jet water, that is, the elastic restoring force of the self by the jet water disappearing. Since the weft ends are held in contact with each other, when the weft ends are held, the action of jet water on the weft ends has already stopped and the wefts are loosening, so the wefts are tense. There is a problem that the weft ends cannot be held in this state. In the latter technique, the catch plate is returned from the weft gripping position to the non-gripping position after the beating operation is completed, so that the tip of the weft thread is gripped by the catch plate in a tensioned state and beaten in that tensioned state. Therefore, there is a problem in that the weft tension of the cloth on the side opposite to the weft insertion side is abnormally increased with respect to the warp tension, resulting in a so-called "weft sink" weaving defect.

The present invention has been made in view of the above problems, and an object of the present invention is to weave a high-quality woven fabric by beating with a proper tension applied to the tip of the weft yarn on the opposite weft insertion side. And

[0006]

For this reason, according to the present invention, a pair of holding members are arranged at the arrival position of the weft end portion on the side opposite to the weft insertion side with the weft flight path sandwiched between the weft ends after weft insertion. A drive device is provided for gripping the weft end portion between the pair of holding members during a period when the portion is under tension, and thereafter driving the gripping portion to release the grip before beating. It is a thing.

[0007]

According to the above construction, the weft tip is held between the pair of holding members in a state where the weft tip is tensioned on the side opposite the weft insertion side to maintain the tension, and then the weft is beaten. By releasing the grip before the wefts lose their freedom, the wefts are allowed to move freely during a certain period after the release until the beating. This free movement of the weft thread relaxes the tension of the weft thread on the reverse weft insertion side and balances the tensions of the warp thread and the weft thread at a high level, so that a high-quality woven fabric can be woven.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment applied to a water jet loom.

The weft yarn 1 is put into the opening of the warp yarn 3 by the water jet nozzle 2 and beaten by the reed 4 onto the cloth fell 5 to be woven as the woven fabric 6. Warp 3 on the opposite side of the warp 3 row
Similarly, a plurality of yarn end treatment yarns 7 that are opened and closed are provided. 8 is a guide plate, 9 is a false twist spindle,
10 is a spindle bracket, 11 is a drive pulley, 1
2 is a belt, and 13 is a driven pulley. Here, a weft end holding device 16 attached to the frame 15 of the loom is provided at the arrival position of the weft end portion on the reverse weft insertion side (on the side opposite to the weft insertion side of the yarn end treated yarn 7).

The weft end holding device 16 will be described with reference to FIGS. 2 and 3 together. Loom frame 15
Brackets 21 and 22 are attached to a support plate 20 fixed to the shafts 23 and 22, respectively.
Holds 24. Here, each of the two shafts 23 and 24 extends in the front-rear direction of the loom, and is provided at a predetermined interval above and below the weft flight path. And, these shafts 23, 24 are respectively provided with plate-shaped holding members 25, 2
The edge of 6 is rotatably attached. Holding member 2
Reference numerals 5 and 26 denote curved portions 25a and 26a on the shafts 23 and 24 side.
And a flat portion 25b which is continuous with this and is capable of surface contact with each other,
26b, and a large number of drain holes 27 are formed in the flat portions 25b and 26b.

An L-shaped bracket 28 is also attached to the support plate 20, and a sponge stopper 29 is attached to the upper surface of the bracket 28. Then, the lower holding member 25 is placed on the stopper 29, whereby the position of the lower holding member 25 is almost fixed.
Then, the upper holding member 26 is placed on the lower holding member 25, and in this state, the pair of holding members 25, 2
6 is a curved portion 25a on the side facing the water injection nozzle 2,
The opening portion 30 is formed with a gap between the portions 26a that is narrower toward the anti-weft insertion side, and the flat portions 25b and 26b are in surface contact with each other on the anti-water injection nozzle side to form the contact portion 31. It is like this.

A permanent magnet 32 is fixed to the upper surface of the upper holding member 26. An L-shaped bracket 33 is attached to the support plate 20 so as to be located above the upper holding member 26. On the lower surface of the bracket 33, a sponge stopper 34 is attached so as to face the upper holding member 32, and an electromagnet 35 is fixed so as to face the permanent magnet 32.

The polarity of the electromagnet 35 changes according to the energization direction (+-) controlled by the energization direction control circuit 36. When the electromagnet 35 is in the + direction, the electromagnet 35 is a permanent magnet 32.
It becomes the same pole as and repels the permanent magnet 32. The energizing direction control circuit 36 includes a loom main shaft 37.
Proximity switch 39 opposed to the action piece 38 attached to the
When the high portion 38a of the action piece 38 faces the proximity switch 39, the energization direction is switched to one direction. The timing of this switching is after the weft insertion and when the jet water is acting on the end of the weft 1. Further, the high portion 38a is formed so that the energization can be switched to the other direction before beating. The action piece is composed of a pair of mating cams so that the switching period of the energization direction can be adjusted.
It is preferable to be able to adjust the existing range of. Here, the drive device is configured to include the electromagnet 35, the energization direction control circuit 36, and the like.

The brackets 21 and 22 are provided on the support plate 20.
However, the size of the opening 30 is adjustable so that the size of the opening 30 can be adjusted. The brackets 28 and 33 are also movably provided so that the pressure contact force between the holding members 25 and 26 can be adjusted.

Next, the operation will be described with reference to FIGS. 4 and 5 together. In FIG. 4, a drum type weft storage device is illustrated, and a locking pin 53 driven by a solenoid 52 to lock the weft 1 wound and stored on the drum 51 is connected to the drum 51. It is designed to be controlled by entry and exit.

Before weft insertion, the high portion 38a of the action piece 38 is not opposed to the proximity switch 37, and the energization direction control circuit 3
The energization direction of the electromagnet 35 by 6 is the + direction. Therefore, the electromagnet 35 has a different pole from the permanent magnet 32, attracts the permanent magnet 32, and integrally moves the upper holding member 26 upward (shown by the dotted line in FIG. 2) to form a lower holding member 25. A weft flight path is formed between them. The upper holding member 2
During the upward movement of 6, the holding member 26 comes into contact with the stopper 34 made of sponge to receive a cushioning action, and the upward movement position is restricted to prevent the permanent magnet 32 from coming into contact with the electromagnet 35.

The warp yarn 3 is opened by the opening device (not shown) as shown in FIG.
It is opened and closed in a sine curve as shown in.
Further, the reed 4 is also swung in synchronism therewith, and when the warp 3 is closed, the reed 4 is beaten. Then, when the opening of the warp 3 becomes a size suitable for weft insertion, weft insertion is started. At the time of weft insertion, water injection from the water injection nozzle 2 is started, and then the locking pin 53 is retracted from the weft storage drum 51 by the solenoid 52. As a result, the weft 1 is transferred to the drum 51
While being unwound, the water is injected into the opening of the warp 3 by the water injection of the water injection nozzle 2. Then, the water jet from the water jet nozzle 2 is stopped at an appropriate timing.
4 continues to fly on the water W already jetted as shown in FIG. 4 (A).

After that, the locking pin 53 is pushed in by the solenoid 52 in the weft storage drum 51, and when the weft 1 is disassembled by a predetermined number of turns, the weft 1 is locked by the locking pin 53 and the weft insertion is completed. To do. Immediately after this, the jet water W is still acting on the end portion of the weft yarn 1, and the weft yarn 1 is in a tension state due to the traction force of the jet water (see FIG. 4 (B)).

In this way, after weft insertion and when the jet water acts on the weft yarn end, in other words, before the jet water has finished passing, the weft end holding device 16 holds the weft yarn 1. Specifically, the weft yarn end holding device 16 holds the weft yarn 1 at the timings shown in FIGS. 4 (B) and 5.
That is, at this timing (actually, slightly before the delay time is expected), the high portion 38a of the action piece 38 faces the proximity switch 37, and the energization direction of the electromagnet 35 by the energization direction control circuit 36 is the-direction. Switch to. Therefore,
The electromagnet 35 becomes the same pole as the permanent magnet 32, and the permanent magnet 32
Repulsing and moving the upper holding member 26 downward
The weft 1 is held between the lower holding member 25 (shown by the solid line in FIG. 2). At this time, the sponge stopper 29
Acts as a buffer.

During this holding, the pair of holding members 2
Although there is jet water between 5 and 26, since water can be discharged through the water drain hole 27, smooth holding is ensured.
This is because if it is a simple plate-like body, the jet water interferes and the plate-like body cannot contact, the holding of the weft 1 is delayed, and the weft 1 begins to loosen. In this way, after the weft insertion and when the jet water is acting on the end portion of the weft yarn 1, in other words, before the jet water has finished passing, the weft end holding device 16 holds the weft yarn 1. Thereby, the weft 1 can be held in a tension state.

Then, as shown in FIG. 4 (C), the jet water passes through the weft end holding device 16 and the proximity switch 37 and the action piece 38 until the weft 1 is pushed out by the reed 4 to the vicinity of the cloth fell 5. Continue relative to the high portion 38a. Therefore,
The tension of the weft 1 is maintained. Immediately after this, Takabe 38
When the a and the proximity switch 37 are finished relative to each other, the energization direction of the electromagnet 35 by the energization direction control circuit 36 becomes the + direction. Therefore, since the electromagnet 35 has a different polarity from the permanent magnet 32, the permanent magnet 32 is attracted to the electromagnet 35 and moves upward, and thus the holding member 26 moves upward (shown by the dotted line in FIG. 2), and the lower holding member A weft flight path is formed between the weft yarns 25 and 25, and the holding of the weft yarn 1 is completed, and the next weft insertion is prepared.
At this time, the sponge stopper 34 acts as a buffer. At this time, since the warp 3 is still slightly open, the warp 3 may be contracted by the weft 1 itself or the tension of the warp 3.
Although there is a restriction due to the balance with the tension and the frictional resistance of the weft yarn 1, the weft yarn 1 can shrink, so that this shrinkage occurs on the reverse weft insertion side of the woven fabric 6, and the tension balance between the warp yarn 3 and the weft yarn 1 becomes 1 Tension is improved at high level. Even after the jet water has passed through the weft yarn end retainer 16, the weft yarn 1 is in a tensioned state for a short time immediately after this, so if this is the case, hold the weft yarn 1 in the tensioned state. Is possible. However, the length of the weft yarn to be inserted is increased so that the weft yarn end holding device 16 moves the weft yarn 1
If the length up to the end of the weft is long, it is possible to hold the weft in a tensioned state for a considerable time even after the jet water has passed through the weft end holding device 16. The yarn length becomes long, which is uneconomical.

Next, as shown in FIG. 4 (D), when the weft 1 is beaten, the warp 3 moves from the closed state to the open state of the opposite phase and is pressed by the reed 4, so that the weft 1
Has no degree of freedom and its tension state does not change even if the holding by the weft end holding device 16 is released.

In this embodiment, the electromagnet 35 as a driving device is used to perform not only the closing operation (weft holding operation) of the pair of holding members 25 and 26 but also the opening operation (weft flight path formation). However, the energization to the electromagnet 35 may be stopped except during the weft holding period, and the opening operation may be performed by the force of the jet water. Further, in this embodiment, the weft end holding device 16 is separated from the reed 4 and is a frame 15 of the loom.
Although it is fixedly provided on the reed 4, it may be provided so as to move integrally with the reed 4. Further, it can be applied to an air jet loom in addition to the water jet loom of the above embodiment.

[0024]

As described above, according to the present invention, the weft yarn is held by the weft end holding device while the tip portion of the weft yarn is strained by the weft inserting fluid flow, and the weft yarn just before beating is still free. Since the holding is continued until a certain time, the tension of the weft can be lowered to the extent that the tension with the warp is not lost while keeping the weft tension at an unprecedentedly high level, so that a high-quality woven fabric can be woven. effective.

[Brief description of drawings]

FIG. 1 is a perspective view of a water jet loom showing an embodiment of the present invention.

FIG. 2 is a front view of a weft end holding device.

FIG. 3 is a plan view of a holding member.

FIG. 4 is an explanatory diagram of holding timing.

FIG. 5: Hold timing chart

[Explanation of symbols]

 1 Weft 2 Water injection nozzle 16 Weft end holding device 23, 24 Shaft 25, 26 Holding member 27 Water drain hole 29 Stopper 32 Permanent magnet 34 Stopper 35 Electromagnet 36 Energizing direction control circuit 39 Proximity switch

Claims (1)

[Claims] 1. A weft end holding device for holding an end portion of a weft thread, which has been wefted by a jet fluid in a jet loom, in a tensioned state, wherein a weft flight path is sandwiched at a reaching portion of the weft end portion on the opposite weft insertion side. After arranging a pair of holding members with each other, the weft ends are held between the pair of holding members after weft insertion and the weft ends are tense, and after that, the grip is held before beating. A weft yarn tip holding device for a jet loom, which is provided with a driving device that drives the yarn to open.